Shell-stitch sewing-machine.



H. R. HUGHES, ja.

SHELL STITCH SEWING MACHINE.

APPLICATION msn sPT.1e,1915.

Patented Jan. 14.1919;

4 SHEETS-SHEET l.

R. R. HUGHES, JR.

SHELL rsmcrlsiwm; MAcHlNE.

APFLICATIQNFILED SEPT- l6| 1915.

Patented Jan. 14, 1919.

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lllllll- R. R. HUGHES. JR.

SHELL STITCH SEWING MACHINE.

APPLICATION FILED SEPT. Ie. uns.

`1,291,526. Patented 13.1.14, 1919.

R. R, HUGHES,'J.

SHELL STITCH SEWING MACHINE. APPLICATION FILED sEPT.16.|915.

Patented Jan. 14, 1919.

4 SHEETS-SHEET 4.

'to provide a stitch-forming mechanism of UNTTED STATES PATENT onirica.

ROBERT R. HUGHES, JR., OFNEW YORK, N. Y., ASSIGNOR T0 UNION SPECIAL MACHINE COMPANY, CHICAGO, ILLINOIS, A. CORPORATION. OF ILLINOIS.

SHELL-STITCH SEWING-MACHINE.

. lowing is a description, reference being had to the accompanying drawing and'to the figures of reference marked thereon.

The invention relates'to new and useful in'iprovements in sewing machines, and more particularly to the stitch-forming mechanism of a machine adapted to form shell 15 stitches,

An object of the invention is to provide a stitching mechanism 'wherein a thread hook, without any latch, may be used to coperate with the needle in concatenating the thread loops. p

' A further object of the invention is to provide a stitch-forming mechanism of the above character wherein the hook coperating with the needle above the work support is oscillated about a longitudinal axis for positioning the hook to engage 'the needle thread and for positioning the hook to shed the previously formed needle loop therefrom.

the above character wherein the hook cooperating with the needle above the work support is mounted upon a support which is moved lendwise and which is oscillated.

'. for properly positioning the hook so that a loop of needle thread extending beneath the work support may b e carried to the edge ofthe fabric and aI loop of needle thread from above the work support carried by said hook through said previously formed loop.

A still further object of the invention is to provide a machine of the above character with a feeding mechanism for feeding the fabric, which feeding mechanism may be controlled so as to shift the fabric after certain groups of stitches have been formed.

In the drawings, which show by way of illustration one embodiment of the invention 1 Figure l is a front view of a portion of a machine havingniy improvements applied thereto Specication of Letters Patent.

A Stm further Object of the invention Patented Jan. 14, 1919.

Application iled September 16, 1915. Serial No. 51,022.

Fig. 2 is a view, partly in vertical section and partly in end elevation, of said ma*- chine;

Fig. 3 isa view, partly in horizontal section and partly in plan, showing the feeding mechanism, the hook coperatmg with the needle beneath the work sup ort, the hook coperating with the needle a ove the-work support, and the mechanisms for operating the same;

Fig. 4 is a vertical sectional view through the feed-controlling cam and the operating parts therefor;

. Fig feed dog and supporting bar therefor;

,Fig 6 is a detail in side elevation showing themain feed bar and the cam for raising` and lowering the same; v

Fig. 7 is a detail'n side elevation of the spring for holding the feed dog in ineiective position;

Fig. 8 is a view showing, more or less diagrammatically, th'e needle and the coperating hooks at the time when the lower hook is first entering the needle loop;

Fig. 9 is a similar View showing the upper hook entering Athe needle loop carried by the lower. hook;

Fig. 10 is a similar needle loop shed from the upper hook passing View showing the engagement with the needle thread above Fig. 11 is a similar-view showing the hook in engagement with the needlethread above the work support; g Fig. 12 is a similar Viewl showlng the up- 51S a dean in Side elevation of uwl l the lower hook and intol the same for per hook in position for shedding the lower '.hookis oscillated back and forth, while the which a hook coperates beneath upper thread hook Vis movedendwise and is oscillated so as to position'the same for engagement withthe needle thread and for properly shedding the needle loop from the shank oi the hook. The feeding mechanism isoperated so as to feedthe fabric after certain groups ofstitches have been formed. This feeding mechanism is adjustable so that the timeof feed may be varied, thus varying the number of stitches formed in each completed shell before the fabric is positioned for forming the next shell.

Referring more in detail 'to the drawings, I have shown my invention applied to a sewing machine having a bed plate 1 carrying an overhanging arm 2 in which a needle bar 3 reciprocates, carrying a needle 4. The needle 4 is supplied with a needle thread n.

Coperating with the needle beneath the work support is a lower thread hook 5. This thread hook is carried by a support 6 which is pivoted at 7 to a suitable bracket 8 carried by the bed plate 1. This support 6 is oscillated by a'link .9 which is ivoted at l0 to the sup-port and is connecte other end to a crank 11 carried by a disk 12 mounted to rotate on a bearing carried per endy to said arm 32 and is pivoted at its'lower'end to this bearing 22. `The bearsleeve 21 in which the looper shaft 19 isl .mounted is pivoted at 41 to its supporting bythe bracket 13 which supports the main y shaft 14. A beveled gear 15 is attached to the disk12, and this beveled gear meshes Ase with a second beveled' gear 16 which is fixed to the shaft 14. As the shaft 14 rotates, the disk 12 will rotate and, through the crank 11, oscillate the thread hook 5 back and forth. This thread hook is timed so as tomove between the needle thread'and the body of the needle when said needle is substantially at the lower end" of its stroke and forms the needle loop beneath the work support which work support is indicated at 17 in the drawings.

Coperating with the thread hook 5 beneath the work support and the needle 4 above the work support is a second or upper thread hook 18. This thread hookis mounted' in a socket in a'looper supporting shaft 19and is held therein by a setscrew 20.` The shaft 19k is journaled in a sleeve 21 so that said shaft may not on'ly oscillate with the sleeve Ybut move freely endwise therein. Said shaft is also, journaled in a I bearing 22. The shaft is moved endwise by means/of a link 23 which is pivoted atv 24"to a sleeve 25 held from endwise movement on the looper shaft by fixed collars `26. The link 23 is pivoted to an arm 27 carried by a transverse shaft 28 which is journaled in a bracket'29- This shaft carries a second arm 30 which is connected to an eccentric strap 31 coperating with an eccentric on the main shaft 1 The bearing 22 is suspended-from an arm 32 mounted on a shaft 33 journaled inA a bracket 34. A link 35 is pivoted at its up-Y bracket 29, and the arm. 36 and the groove in which it works are both curved .about this center 41. Splined to the looper shaft 19 is a gear 42. This gear 42 meshes with a rack 43 which is secured by screwsl 44 to the bracket 34. The 4gear 42 is held from endWise movement relative to the shaft 19 by a yoke'45 which yis fixed to the bearing 22 and is provided with pins or balls running in a groove 46 formed in the hubv of the gear 42. The rack 43 is also curved about the center 41. The shaft 33 is oscillated by an arm 47 which is connected to a pitman 48 which, in turn, coperates with an eccentric on the main shaft 14.

The fabric is held on the work support 17- by a presser foot 49 which is fixed to a presser bar 50 mounted in the overhanging arm of the machine.l A feed dog 51 en`' gages the fabricunderneath the presser footI 49 and feeds the same so as to properly position the fabric for the formation of the shell stitches. This feed dog. 51 is formed integral with a bar 52 which is supporte'dby a main feedba'r 53. This mam feed bar 53 is pivoted at 54 to the feed rocker 55 which, in turn, is pivoted at 56 to the bed' plate 1. The feed rocker 55 is moved back and forth by a link 57 which is connected to an' adjustable crank in 58 carried by the end ofthe main sha 14.' The main feed bar 53 is raised and lowered by an eccentric 59 4mounted on the shafti14. his eccentric under face of the main feed bar -and a bracket arm 61 which is also secured yto this main feed bar. The main-feedbar 53 is formed with a groove or recess in its upper face extending substantially from end to end thereof and the bar' 52 carryin the dog 51 is located in this recess. Said ar 52 is secured to the main feed barb a pivot pin 62. A spring 63 is secured to t of the main feed bar by screws 64, and this spr-,ing rests upon the upper face ofthe bar 52 and holds the feed dog 51 depressed. The' main feed bar 53 and the eccentric which raies and lowers the same are so formed tha ,when the feed dog 51 is depressed b this spring-63, the feed dog will move back and forth with the movement of the feed bar without engaging the material. The feed bar isfraised into engagement with the ma- 'terial by a controlling cam 65. This cone' upper face preferably `plate 1. Said controlling cam is mounted on .a pawl 69. This pawl is pivoted by a pin w to an arm 70 mounted so as to oscillate freely on the shaft 66. A spring 71, shown in dotted lines in Fig. 2, normally holds the pawl in engagement with the ratchet wheel 68. The arm 70 through the medium of a pin is connected by a link 72 to an adjustable stud 7 3 fixed to a bracket arm 74 mounted on the feed rocker 55. This stud 73 is mounted in a segmental slot 75 in the arm 74. By adjusting the stud upwardly in the slot, the throw of the arm 70 may be increased, while an adjustment of the stud downwardly inthe slot decreases the throw of the arm. By this adjustment, the throw of the pawl 69 may be varied, and thus the time interval, when the controlling cam 65 becomes effective to raise the feed dog into engagement with the fabric, may be varied. The bar 52 is formed with a downwardly projecting lug' 76 which projects through a slot 77 in the main feed bar 53, and this projecting lug lies in the path of travel of the controlling cam 65. As herein shown, this controlling cam is formed in two parts which are equally spaced. When the controlling cam 65 strikes the lug 76, then the feed bar 52 will be turned about its pivotal connection so as to raise the feed dog 51 into engagement with the fabric. That is to say, when the feed dog is raised by the controlling cam, then the fourmotions given to the main feed bar 53 cause the feed dog to become effective to feed the material as long as this bar is raised., As soon as the eontrolling cam 65 passes from beneath the lug 7 6, then the` spring will throw the feed bar downward and position the feed dog so that it becomes ineffective in its movements.

From the above, it will be apparent that I may control the feed dog which is moved back and forth for each rotation of the shaft so that said feed dog will only feed the material after a certain number of rotations of the shaft. Thus, the fabric may be positioned for the formation of the shell stitch, and the needle will enter the fabric substantially in the same place for a plurality of reciprocations, after which the fabric is moved and the needle positioned for the next shell. By varying the throw of the pawl which turns the ratchet wheel moving the controlling cam, I may vary the period of time the feed dog remains in its ineffectiveposition, and consequently vary the number of stitches formed in each shell, that is to say. the pawl may be caused to feed two, four or siX teeth at every stroke, and;by adjusting the throw of the pawl groups of stitches varying from four stitches to4 eighteen or `twenty stitches for each shell may be made. By adjusting the crank pin 58, the feed travel may be varied and consequently the distance between successive shells may bc varled. il

In the operation of my device, the needle passes through the fabric on the work support and rises slightly to form the needle loop and then the lower hook 5 moves-into said loop and carries the same toward the edge of the fabric. hook 18 is being lowered and turned. lVhen the hook 5 reaches substantially the forward end of its stroke, the hook 18 is completely lowered and turned and is substantially in the position shown in Fig. 9. 18 has a beak 78 and has a point 79 which is slightly defiected 'upwardly relative to the beak 78 and laterally relative to said beak, as shown in Figs. 9 and 10. An oscillation of the shaft 33 causes the hook torise up against the under face of the needle loop, as shown in Fig. 9, and to enter the needle loop when said hook moves forward, as shown in Fig. 10. The forward movement of the hook is caused, as above noted, by the oscillation of the shaft 38 which reciprocates the looper shaft 19 in its bearings. As the looper shaft 19 is raised to bring the hook 18 above the plane of the work support, the gear 42 running on the rack 48 will oscillate the hook so as to bring its beak 78 into substantially a horizontal plan-e, as shown in Fig.10. The needle rises to the upper end of its stroke, as shown in Fig. 11, and this beak 78 engages the thread between the needle eye ythe strands thereof. In other words, by this oscillation of the hook` l am enabled to move the hook through one needle loop and engage the needle thread to form another At the same time the A This hook needle loop and draw this second needle loop through the rst needle loop without the use. of a loop-shedding latch. The hook 18. when it sheds the lower needle loop, as shown in Fig. 12, carries the upper loop through this lower needle loop and` when this hook moves forward to enter the next needle loop formed beneath the work support, that is, to the position shown in Fig. 9, this upper thread loop will be still retained by the thread hook 18 and the movement of theV thread hook 18 underneath the new needle loop lifts this new needle loop up through thepreviously formed upper needle loop and sheds. this upper formed needle loop from the hook. In other words, first a needle loop is formed above the material and carried through a needle loop formed bea 4 V weies neath the material,l after which theloop` formed 'beneaththe materiall is carried through the next needle loop formed above the material. The curving of the point of the hook 18 serves to retain this lowerr needle loop-on the shank thereof when the hook'is moved into the lower needle loop, as shown in Figs. 9 and 10.

In Fig. 13 of the drawings, I have shown the fabric at f and the loops, which are interlocked to form the shell stitches, are indicated at s. The needle punctures are'indi- 'cated at a. It will be noted that the needle enters the fabric at the points indicated at ment of parts may be made without departing from the spirit 'of the invention, as set forth in the appended claims. Having thus described my invention, what I claim as new and desire to secure by Let ters-Patent is 1. The combination of a work support, a

thread carrying needle a thread hook cooperating with the needle 'beneath the work support, a second thread hook adapted to pass through the loop formed by the firstnamed thread hook and engage the needle thread above the .work support to form a `loop thread therein and draw the same through the first-named thread loop.

2. The combination of a work support, a4 threadlcarrying needle, a thread hook, means for operating said thread hook for engaging the needle thread beneath the work support the same whereby said hook is caused toV to form a thread loop therein, a second' thread hook, means for reciprocating said last-named thread hook and for oscillating enter the loop formed beneath the work support, engage the needle thread above the work support, form a'loop therein, and draw the same through the first-named loop.

3. The combination of a work support, a thread carrying needle, a thread hook cooperating with the needle beneath the work support, a thread hook coperating with the needle above the work support, means for o erating' said last-named thread Ahook w ereby a loop is formed in the needle thread above the work support and the loop of thread formed in the needle thread beneath the work support by the first-named thread hook is engaged by said second thread ,hook and carried through the needle loop formed above the work support.

4. The combination of a work support, a

thread carrying needle, a thread hook cooperating with the needlebeneath the work support, a thread hook coperating with the needle above the work support, means alor operating said last-named thread hooi-z whereby the same is reciprocated and oscil.mv

lated and caused to engage the needle thread above the work support and form a loop therein, also to engage the needle loop from beneath the work support and carry the same through the needle loop formed by said last-named thread loop above the work supl port, and also to -form another thread loop in the needle thread above the work support and carry the same through said needle loop formed beneath the work support.

5. The combination of a work support, a' i thread carrying needle, a thread hook cooperating with the needle beneath the work deflected point adapted to enter 'the needle loop formed Vbeneath the work supporgand a hook in rear thereof adapted to engage the' needle thread above the work support, means support, a thread hook having a laterally for operating said last-named thread hooky whereby thesame is reciprocated and oscillated and caused to engage the needle thread f I above the work support and form a loop therein, also to engage the needle loop from beneath the work support and carry the same through the needle loop formed from the needle thread above the work support, and also to form another threadloop, in the needle thread above the work support and carry the same through said needle loo formed beneath the workV support.

6. The combination of a work support, a thread carrying Aneedle,va 'thread hook lcooperating with the needle beneath the work support, a thread hook coperating with the needle above the work support, said ,lastnamed 'thread hook having its pointvdefiected away from its beak and laterally of its beak to assist in retaining the needle loop from) beneath the work support on ysaid thread hook;

7. The combination of a workA support, a4

thread carryingneedle, a thread hook cooperating with the needle beneath the work support, means for oscillating said thread hook, an upper thread hook coperating with the needle above the work support and with the irstmamed thread hook beneath the work support, means for reciprocating said upper thread hook and for oscillating 4the same whereby the beak of said upper thread hook is positioned horizontally for engagement with the needle thread and is positioned substantially 'vertically tofacilitate the shedding of the under thread loop from the shank ofV said upper hook, said up'- per thread hook having its point bent outwardly away from the beak and laterally of the beak to assist in retaining the needle Sid thread loop when said upper thread hook is entering the needle loop from beneath the work support.

8. The combinationof a work support, a.

oted sleeve in which said shaft is mounted to reciprocate and oscillate, means forfreciprocating theshaft in said sleeve, and means for oscillating the shaft as it is reciprocated.

9. The combination of a work support,'a thread carrying needle, a thread hook cooperating with the needle beneath the work support, a thread hook cooperating with the needle above the work support and with said hook beneath the work support, a shaft-carrying said last-named thread hook, a pivoted sleeve in which said shaft is mounted to oscillate and to reciprocate, means to reciprocate said shaft, a gear splined on said shaft, a stationary. rack engaged by said gear, and means for bodily swinging said shaft, said' gear operating to oscillate the shaft during its bodily swinging movement.

10. The combination of a work support, a thread carrying needle, a thread hook co' operating with the needle beneath the work support, a thread hook coperating with the needle above the work support and with said hook beneath the work support, a shaft carrying said last-named thread hook, a pivoted sleeve in which said shaft is mounted to reciprocate and oscillate, means for reciprocating the shaft, a bearing between said sleeve and said hook for said shaft, means for raising and lowering said bearing, a guide curved about the pivot of said sleeve as a center for guidingsaidbearing in its up and dowr movements.

11. The combination of a worksupport, a thread carrying needle, a thread hook cocperating'with the needle beneath the work support, a thread hook eoperating with the needle above the work support and with said hook beneath said work support, a shaft carrying said last-named thread hook, a pivoted sleeve in which the shaft is mounted to reciprocate and oscillate, means for reciprocating the shaft, a bearing between the sleeve and said hook for the shaft, means for raising and lowering said bearing, a stationary rack curved about the pivot for said sleeve as a center, a gear splined to said shaft and carried by said bearing and meshing with said rack for oscillating said shaft.

12. The combination of a work support, a

thre'ad carrying needle, a thread hook cooperating With Said needle beneath the work support, a thread hook coperating with the needle 'do the work support and with said hook beneath the w'ork support, means for reciprocating andoscillating 'said last named thread hook whereby. loops are formed in the needle thread, which loops are locked successively one with the other, and a feeding mechanism including a feed dog, means for reciprocating said feed dog, and means for rendering said feed dog ineffective t0 engage the fabric during a plurality of reciprocations of the needle. r

13. The combination of a work support, a thread carrying needle, a thread hook cooperating With the needle beneath the work support, a thread hook coperating with the.

needle above the work support and With said 'hook beneath the work support, means for reciprocating and oscillating said lastnamed thread hook whereby loops are formed in the needle thread beneath the Work support which loops are locked successively one with the other, and a feeding mechanism including a feed'dog, means for reciprocating said feed dog, and means for rendering said feed dog ineffective -to engage the fabrlc during a plurality of reciprocations of the needle, said last-named means including devices which may be adjusted for varying the time interval when said feed dog becomeseii'ective to feed the fabric.

14. The combination of a work support, a needle, a thread hook,'means for operating the thread hook whereby the same is caused to pass into a needle loop formed beneath the work support, engage the needle thread above the work support and draw the same through the first named needle loop for forming shell lstitches and a feeding mechanlsm for feeding the material, including means for giving the material a feeding movement after a'predetermined number of shell stitches have been formed and means whereby the length of the feed movement may be varied. A

15. The combination of a work support, a needle, a thread hook, means for operating the thread hook whereby the same is caused to pass into a needle loop formed beneath the `work support, engage the needlel thread above the work support and draw the same through the first named needle loop for form-V hook coperating with the'needle beneath the work support, a thread taking implement co.- operating with the needle above the work support and with said hook beneath the work support, said implement having' a thread engaging hook, means for moving said imple ment above and below the work support and for oscillating the ir lement whereby said hook is substantiall horizontal while engaging the needle thread above the work support and is substantially vertical while passingI into and out of the needle loop formed beneath the work support.

17. A sewing machine including 'in combination, a work support, a needle, a thread hook coperating With the needle beneath the work support, a thread taking implement cooperating with the needle above the .work support and with said hook, said thread taking implement having a hook for engaging the needle thread, means for engaging the a needle thread, means for moving the thread the first-named loop-forming nnplement beneath the work support and with the needle above the work support, said second-named loop-forming implement havinga `hook on one face thereof for engaging the needle ,aanwas thread above the work support and an upturned point for engaging the loop formed in. the needle thread beneath the work support whereby said second-named loop-forming implement may pass through the loop formed in the needle thread beneath the work support by the first-named loop-forming implement and engage the needle thread abqye the Work support and form a loop therein. .1

19. A sewing machine including in combination, a work support, a needle, a hook co-4 operating with the needle beneath the work support, a loop-,forming implement coperating with the hook and with the needle above the work support, said loop-forming implement having a hook on one side face thereof, means for raising and lowering said loopyforming implement, and, means for oscillating thessame, said oscillating means including devices whereby the hook is given a dwell .in its upper and lower position, and means for movmg said loop-fprming -implement bodily endwise.

ln testimony whereof, I aliix my signature, p

in the presence of two witnesses.

ROBERT R. HUGHES, JR. v

Witnesses:

S. GEORGE Tarn, A. F. BRnnsrrALL. 

